Number One Observatory Circle is the official residence of the Vice President of the United States.
Located on the grounds of the United States Naval Observatory in Washington, DC, the house was built in 1893 for its superintendent. In 1923, the chief of naval operations loved the house so much that he booted the superintendent and made the house his home. In 1974 Congress refurbished the house and turned it into the official residence of the Vice President.
Although Number One Observatory Circle was available to the Vice President in 1974, three years passed before a Vice President lived in the home. Vice President Gerald Ford became President before he could use the home, and his Vice President, Nelson Rockefeller, only used the home for entertaining since he already had a residence in Washington. Vice President Walter Mondale was the first Vice President to move into the home and every Vice President since has lived in that house.